Incased heating unit



Nov. 27, 1928. y 1,693,421

J. c. wooDsoN INCASED HEATING UNIT Filed March 31. 1927 WITNESSES: INVENTOR y. James C. Woodson. m" lhmzm/ f 'ATTORNEY PATENT- orrics.

' JAMES C.`WOODSON, OF MANSFDELD, OH, I0, ASSIGNOR TO KANUFACTUBIN'G COMPANYyA CORPORATION WESTD'GHOUSE ELECTRIC OF PENNSYLVANIA.

HEATING UNIT.

- Application tiled Karch 31,1927. Serial No. 179,730.

My invention relates to electrical heating units and more particularly to ineased heating units for outdoor use.

An object of my invention is to provide a relatively simple andeasily manufactured incased heating unit.

Another object-of my invention isto [provide anincased heating unit that shall ave a ground terminal associated therewith.

In practicing my invention, I provide al tubular casing, removable end closure members therefor, metal stri s within the'A casing extendin laterally t ereof at the respective ends o the casing, a heating unit embodying a metal supporting member and refractory resistor supports therein together with a resistor, water-tight terminal members for theA resistor, and 'a ground terminal clamped against the outer surface of the casing at one end thereofby the spaced radially-extending watertight terminal members. In the drawings,

Figure 1 is a view, in longitudinal section, of a heating unit embed ng my invention.

Fig. 2 is a view, in ateral section therethrough, taken on the line II-II of 'Fig'. 1,

and

of'some standard size, the two endsthereo -being provided with threads to permit of mounting end closure members 13v and 14 thereon'l 'Iwo metal strips 15 and 16 are located within the tubular casing adjacent to each end thereof extending laterally ofthe casing; the two ends of ewc'h strip welded'to 'the inner surface of the casing, asshown more particularly in Figs. 2 and 3 of the'drawings.

The vstrips-15 and'16 serve as supporting members for a heating unit 17 located within the casin v and extending longitudinally thereof. 'he unit 17 com rises a sheet-metal member 18, of substantia y overhung-cha'nnel shape in lateral section, within which are locateda 'plurality of refractorymembers 19 which may be relatively shortin order to permit of easy manufacture and which are..lo cated within the member 18 in end-to-end abutting relation relatively to each other. A plurality of undercut gxooves 21 are provided 1n the re's tive mem rs 19 in suchmanner that all o the grooves are alined longitudinah.

Fig. 3 is anend view witha'ca'p member re-I ly of the heating unit to receivea helically wound resistor 22. The number of undercut grooves 21 is even, in order that both the-beginning and the end of the resistor member 22 may be located at one end of the heating unit proper.

The heating unit 17 is secured to the strips 15 and 16 by bolts 23 and 24, insulating wash- 'ers 25 and 26 being the strips 15 and 16, respectively, to provide additional insulation between the resistor 22 and the vcasing 12. Cooperating nuts and lock washers are mounted on the end of the bolts 23 and 24 to securely against the strips 15 and 16.

The refractory members 19 are prevented from movinglongitudinally of the channel member 18 by washers 27 mounted on the bolt 24 and b an upturned integral portion 28 of the' mem r 18 of channel section, this integral portion being shown at the left-hand end ofFig. 1 of the drawing. ,.The ends of the resistor member 22 are connected to terminals 29 and 30, each of substantially L-shape, one le of which is clamped against the outer'en of a refractory end member 19by a bolt 31 having a nut 32 cooperating therewith in the usual manner.

An additional nut 33 is provided on the outer end of the bolt 31 in order to permit' of securely clamping an end of the resistor 22 against the nut 32, which latter nut is not screwed down tight agiainst the cooperating terminal of L-shape. his is Afor the reason that some relative expansion-will take. lace between the refractory member 19 an the bolt 31 which might `cause-brealring-of the refractory memberifthe .nut 32 were screwed down tightly. fV

Walentight terminal 'members for the de'- vice` are provided, each a metal bushing 34 extending radially intothe ca sprovided on each side of vclamp the member 18*Y mg at one end thereof and havin vcooperating screw'threads to permit of-ma 'g a water-tight- 'oint therebetween.- 35

-of a suita le electric-insulating maman, am

outer end of which is providedwith 'an annu- I lar shoulder, fits into the 'tubular-metal .bush-A ing 34, and a metal .plug A36, also .o`f tubular. shape and having an outer annul!- shoulder portion, has screwthreadedengagement wlth th'e metal bushing 34. z A conductor 37 ex- =tends into the water-tight bushing' and.. has

v its inner end connected to the outer leg por' aan pf a emma memberqby 38L1ii9 Y position and Asbestos string 39 is wound around the con: ductor 37 before the metal plug 36 is screwed into the bushing 34, the inner end of plug 36 being of inverted cone shape so the asbestos string 39 will be compressed, substantially as shown in Fig. 3 of the drawing, to rovide an. inner water-tight joint.

metal strip 41, constituting a name plate and a ground terminal, is securely clamp againstI the arcuate outer surface of the casing to extend laterali therearound, substantially as shown in ig. 3 of the drawing. That part of the strip 41 located between the spaced water-tight terminal members may constitute a. name plate, while anl extending end portion thereof may be provided with a suitable cable terminal 42 to permit of connecting a ground wire thereto in a manner well known in the art.

In building a. heater` of this type, a standard pipe may be cut to any desired length, after which the strips 15 and 16 are weldedv in place from the end openings in the pipe. The previously assembled heating unit 17 may then be mounted in proper operative held on the strips by the bolts 23 and 24, as hereinbefore described. The watertight terminals and conductor leads are then placed in proper operative positions, the ground terminal strip being clamped against the pipe by them and connections made between the conductors 37 extending through the water-tight terminal members and the terminals 29 and 30 of the heating unit proper. The end closure members 13 and 14 the thatt are then mounted i'.. place, being screwed on tightly to make the entire heater watertight.

:Various modifications may be made in the device embodying my invention without de parting from the spirit and scope thereof, and I desire that only such limitations shall be placed thereon as are imposed b the prior art or are set forth in the append claims.

I claim as my invention:

1. In an incased heater, the combination with a tubular metal casing, end closure members therefor, a. heating unit within said casing and waiter-proof terminal members at one end o f said casing, of a ground terminal member secured against said casing by said terminal members. A

2. Means for supporting an electrical-resistance heating element, comprising an elongated member of substantiallv' channel sha-pe in lateral section, a plurality of insulating blocks positioned in said channel, means in the upper faces of convolutions of said heatino' element, and means for retainingsaid blocs in said channel in operative re ation.

3. In an incased electrical heating element having a terminal projecting through and secured to the casingthereof, means constituting a combined ground Aterminal and name plate clamped to said casing by said terminal in electrical Contact with said casing.

In testimony whereof, I have hereunto subscribed my name this 23 daj7 of March 1927.

JAMES c". WooDsoN.

said blocks for spacing the' l 

